A chunk of fur loss

Question
Hi, Dr. Krempels
I have an almost-2 years old rabbit (a Dwarf Hotot).
About a month ago, I found a half of a penny sized patch right next to her
upper lips. It was impossible to notice it because it was where you touch and  
pull up when you try to see rabbit's upper teeth.  I examined that the bold
skin seemed a little swollen and red. Also when I gently touched the spot, I
felt some kind of crispy thing that is stuck on the surface of her swollen skin.
I made an appointment with a vet but I had to wait almost a week. I
continuously examined her patch, and everyday the patch was filled little by
little. And about two weeks later it was completely filled.
The thing is she didn't feel anything when i touched the patch. She ate just
like how much she'd been eating. All the behavior was normal.
However, a month later, today, I found a little bigger patch on the exact
opposite side of her upper lip from where she had one a month ago. No
irritation and no swell. but where the  whisker start from her skin, i can see
some black crispy things stuck on the root of whiskers. Was she bleeding??
There is no sign of open cut though...
she is not bothered at all and behave as normal except she sheds a lot from
few weeks ago which seems normal to me.
Can you please give me some of your advises? Should I wait until the patch
naturally covers itself?
Ps. I raise her as a puppy. I don't take her to outside but she runs around
everywhere in my apartment. i don't think I put any chemicals on the carpet
or on anything that she chews or bites.

Please reply soon,
sincerely,
Elizabeth

Answer
Dear Elizabeth,

The two things that come to mind here are that (1) she might have a mild case of mange mites that are showing up at the corners of her mouth or (2) she has molar spurs or other dental problem that's causing intermittent drooling/salivating.  The latter will burn the skin around the lips and under the chin, and may even make her bleed if she scratches at it.  I suspect that the black things you saw at the base of her whiskers might have been small scabs.

I think it would be wise to get her to a very experienced rabbit vet who has dealt with rabbit dental problems before, and have a good, deep oral exam to check for molar spurs or other dental problems.  Please see:

www.bio.miami.edu/hare/dental.html

and find a good vet here:

www.rabbit.org/vets

If this is simply a bit of mange (caused by microscopic, parasitic mites), then it's easily treated with Revolution (selamectin) from your vet.  Please see:

www.bio.miami.edu/hare/furloss.html

Hope this helps, and that she'll be all smooth and uncrusty soon!

Dana